Calculate the n-day rate of change (ROC) for all periods for which there is sufficient data.
- An series where the first element is the closing price in the last trading period,
the second term is the closing price in the previous trading period and so on.
- The number of days before to which the closing price is compared.
A series where the first term is the rate of change for the most recent
period, the second term is the rate of change for the previous period and so on.
|ArgumentException||Thrown if either parameter is strictly negative.|